CLINICAL PHARMACOLOGY
Mechanism Of Action
Diphtheria
Diphtheria is an acute toxin-mediated disease caused by
toxigenic strains of C. diphtheriae. Protection against disease is due
to the development of neutralizing antibodies to diphtheria toxin. A serum
diphtheria antitoxin level of 0.01 IU/mL is the lowest level giving some degree
of protection. Antitoxin levels of at least 0.1 IU/mL are generally regarded as
protective.6 Levels of 1.0 IU/mL have been associated with long-term
protection.7
Tetanus
Tetanus is an acute disease caused by an extremely potent
neurotoxin produced by C. tetani. Protection against disease is due to
the development of neutralizing antibodies to tetanus toxin. A serum tetanus
antitoxin level of at least 0.01 IU/mL, measured by neutralization assay, is considered
the minimum protective level.6,8. A tetanus antitoxoid level ≥ 0.1
IU/mL as measured by the ELISA used in clinical studies of Quadracel is
considered protective.
Pertussis
Pertussis (whooping cough) is a respiratory disease
caused by B. pertussis. This Gramnegative coccobacillus produces a
variety of biologically active components, though their role in either the
pathogenesis of, or immunity to, pertussis has not been clearly defined. There
is no well-established serological correlate of protection for pertussis.
Because DAPTACEL contains the same pertussis antigens manufactured by the same
process as those in Quadracel, the effectiveness of Quadracel against pertussis
was based on a comparison of pertussis immune responses following Quadracel to
those following DAPTACEL (Diphtheria and Tetanus Toxoids and Acellular
Pertussis Vaccine Adsorbed). [See Clinical Studies]. The efficacy of the
pertussis component of DAPTACEL was determined in clinical trials of DAPTACEL
administered to infants (see DAPTACEL prescribing information).
Quadracel contains twice as much detoxified PT and four times as much FHA as
DAPTACEL.
Poliomyelitis
Polioviruses, of which there are three serotypes (Types
1, 2, and 3), are enteroviruses. The presence of poliovirus type-specific
neutralizing antibodies has been correlated with protection against
poliomyelitis.9
Non-Clinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Quadracel has not been evaluated for carcinogenic or
mutagenic potential or impairment of fertility.
Clinical Studies
Immunogenicity
In Study M5I02, children 4 through 6 years of age
received Quadracel or DAPTACEL + IPOL as the fifth dose in the diphtheria,
tetanus, and pertussis vaccination series and the fourth or fifth dose in the
inactivated poliovirus vaccination series. Subjects also received their second dose
of MMR and Varicella vaccines, concomitantly. The immunogenicity subset
comprised 263 subjects in the Quadracel group and 253 subjects in the DAPTACEL
+ IPOL vaccines group. [See study description in ADVERSE REACTIONS].
Antibody levels to diphtheria, tetanus, pertussis (PT,
FHA, PRN and FIM) and poliovirus antigens were measured in sera obtained
immediately prior to vaccination and 28 days after vaccination. The co-primary
endpoints were booster responses rates and antibody geometric mean
concentrations/titers (GMCs/GMTs) to diphtheria, tetanus, pertussis and
poliovirus antigens elicited after vaccination. Booster response rates and
antibody GMCs/GMTs following Quadracel vaccination were compared to those after
DAPTACEL + IPOL vaccination.
Quadracel was non-inferior to DAPTACEL + IPOL vaccines
administered concomitantly at separate sites, as demonstrated by comparison of
the post-vaccination antibody booster response rates and GMCs/GMTs to
diphtheria and tetanus (Table 2), to all pertussis antigens (Table 3) and to
poliovirus 1, 2 and 3 (Table 4).
Table 2: Booster Responses Rates, Pre- and
Post-Vaccination Seroprotection Rates and Post-Vaccination Antibody Levels to
Diphtheria and Tetanus Antigens Following Quadracel or Concomitant but Separate
DAPTACEL and IPOL Vaccines CoAdministered with MMR and Varicella Vaccinesa
|
Quadracel
(Nb =253-262) |
DAPTACEL + IPOL
(Nb =248-253) |
Anti-Diphtheria |
% Booster Responsec |
97.3d |
99.2 |
Pre-vaccination % ≥ 0.1 IU/mLe |
90.7 |
83.1 |
Post-vaccination % ≥ 0.1 IU/mLe |
100.0 |
99.6 |
Post-vaccination % ≥ 1.0 IU/mLe |
99.6 |
99.6 |
Post-vaccination GMC (IU/mL) |
18.6f |
15.5 |
Anti-Tetanus |
% Booster Responsec |
84.2d |
84.3 |
Pre-vaccination % ≥ 0.1 IU/mLe |
91.7 |
89.1 |
Post-vaccination % ≥ 0.1 IU/mLe |
100.0 |
99.2 |
Post-vaccination % ≥ 1.0 IU/mLe |
98.9 |
96.8 |
Post-vaccination GMC (IU/mL) |
6.4f |
5.5 |
a ClinicalTrials.gov Identifier: NCT01346293.
b N = The number of subjects with available data.
c Booster response: In subjects with pre-vaccination antibody
concentrations < 0.1 IU/mL, a post-vaccination level ≥ 0.4 IU/mL; in
subjects with pre-vaccination antibody concentrations ≥ 0.1 IU/mL but <
2.0 IU/mL, a 4fold rise in post-vaccination level; in subjects with
pre-vaccination antibody level ≥ 2.0 IU/mL, a 2-fold rise in post-vaccination
level.
d Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination booster response rates for diphtheria and tetanus (lower
limits of the 2-sided 95% CIs o f the difference [Quadracel minus DAPTACEL + IPOL]
were > -10%).
e Seroprotection: anti-diphtheria and anti-tetanus antibody
concentrations ≥ 0.1 IU/mL and ≥ 1.0 IU/mL.
f Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination GMCs for diphtheria and tetanus (lower limits of the 2-sided
95% CIs of the ratio [Quadracel / DAPTACEL + IPOL] were > 2/3). |
Table 3: Booster Response Rates and Post-vaccination
Antibody levels to Pertussis Antigens Following Quadracel or Concomitant but
Separate DAPTACEL and IPOL Vaccines Co-Administered with MMR and Varicella
Vaccinesa
|
Quadracel
(Nb =250-255) |
DAPTACEL + IPOL
(Nb =247-249) |
Anti-PT |
% Booster Responsec |
95.2d |
89.9 |
Post-vaccination GMC (EU/mL) |
120.7e |
61.3 |
Anti-FHA |
% Booster Responsec |
94.9d |
87.5 |
Post-vaccination GMC (EU/mL) |
123.5e |
79.0 |
Anti-PRN |
% Booster Responsec |
96.9d |
93.1 |
Post-vaccination GMC (EU/mL) |
282.6e |
187.5 |
Anti-FIM |
% Booster Responsec |
97.2d |
92.4 |
Post-vaccination GMC (EU/mL) |
505.8e |
378.9 |
a ClinicalTrials.gov Identifier: NCT01346293.
b N = The number of subjects with available data.
c Booster response: In subjects with pre-vaccination antibody
concentrations < LLOQ, a post-vaccination levels ≥ 4xLLOQ; in subjects
with pre-vaccination antibody concentrations ≥ LLOQ but < 4xLLOQ, a
4-fold rise in post-vaccination level; in subjects with pre-vaccination
antibody level ≥ 4xLLOQ, a 2-fold rise in postvaccination level.
d Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination booster response rates for all pertussis antigens (lower
limits of the 2-sided 95% CIs of the difference [Quadracel minus DAPTACEL + IPOL]
were > -10%).
e Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination GMCs for all pertussis antigens (lower limits of the 2-sided
95% CIs of the ratio [DTaP-IPV / DAPTACEL + IPOL] were > 2/3). |
Table 4: Booster Response Rates, Pre- and
Post-Vaccination Seroprotection Rates and Post-vaccination Antibody Levels to
Poliovirus Antigens Following Quadracel or Concomitant but Separate DAPTACEL
and IPOL Vaccines Co-Administered with MMR and Varicella Vaccinesa
|
Quadracel
(Nb =247-258) |
DAPTACEL + IPOL
(Nb =248-253) |
Anti-Poliovirus 1 |
% Booster Responsec |
85.9d |
82.3 |
Pre-vaccination % ≥ 1:8 dilution |
98.4 |
98.8 |
Post-vaccination % ≥ 1:8 dilution |
100.0 |
99.6 |
Post-vaccination GMT |
3477e |
2731 |
Anti-Poliovirus 2 |
% Booster Responsec |
78.3d |
79.0 |
Pre-vaccination % ≥ 1:8 dilution |
99.6 |
99.6 |
Post-vaccination % ≥ 1:8 dilution |
100.0 |
100.0 |
Post-vaccination GMT |
3491e |
3894 |
Anti-Poliovirus 3 |
% Booster Responsec |
85.0d |
84.7 |
Pre-vaccination % ≥ 1:8 dilution |
96.8 |
93.1 |
Post-vaccination % ≥ 1:8 dilution |
100.0 |
100.0 |
Post-vaccination GMT |
4591e |
3419 |
a ClinicalTrials.gov Identifier: NCT01346293.
b N = The number of subjects with available data.
c Booster response: In subjects with pre-vaccination antibody
concentrations < 1:8 dilution, post-vaccination levels ≥ 1:8 dil; in
subjects with pre-vaccination antibody concentrations ≥ 1:8 dilution, a
4-fold rise in postvaccination antibody levels.
d Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination booster response rates for polio types 1, 2 and 3 (lower
limits of the 2-sided 95% CIs of the difference [Quadracel minus DAPTACEL + IPOL]
were > -10%).
e Quadracel was non-inferior to DAPTACEL + IPOL based on the
post-vaccination GMTs for polio types 1, 2 and 3 (lower limits of the 2-sided
95% CIs of the ratio [Quadracel / DAPTACEL + IPOL] were > 2/3). |
REFERENCES
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7 Tiwari TSP, Wharton M. Diphtheria toxoid. In: Plotkin
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8 Roper M, Wassilak SGF, Tiwari TSP, Orenstein WA.
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Vaccines. 6th ed. Philadelphia, PA: WB Saunders; 2012:746-72
9 Sutter RW, et al. Defining surrogate serologic tests
with respect to predicting protective vaccine efficacy: Poliovirus vaccination.
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